AOC P/N : 41A50-144 - Manual (Page 18)

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II (a) THE SCREEN is Abnormal , stuck at white screen, OSD window can’t appear, but
keyboard & LED was normal operation.
At general, this symtom is cause by missing panel data or panel power, so we must check our
wire-harness which connected to panel or the panel power controller (U202)
II. (b)The screen had the Vertical Straight Line, might be stuck in Red, Green, Blue
That symptom is cause by bad Panel issue ( might be the Source IC from Panel is cold solder or
open loop ) so REPLACE THE PANEL TO NEW ONE.
Check if the Wire harness from CN601 & CN602 loose?
Check the wire on both Panel-side and Mainboard side.
Check the Panel-Power circuit as above (page 15)
U202 pin 5,6,7,8 ,must be 5V
Yes, tight enough
Yes, Voltage normal
Check the LVDS-Power L603,L604,L601,L602,L900= 3.3V ?
Check the both U601 & U602 LVDS-Input pin 31= 45mhz –
65mhz, and pin 27 = Vsyn freq, pin 28 = 45khz- 65 khz
Yes, Voltage normal
Yes, Frequency normal
Replace both LVDS chip ( U601 & U602)
Tighten it.
Check U904,which convert the 5V to
3.3V
Check U200 DATA-OUPUT block as
above ( page 15)
Check OSCILLATOR Block as
above ( page 15)
NG,no data output
Replace U302 MCU and check it RESET
pin 10 ,must be turn high to low when first
AC power-on
OK,all clock is normal
Replace U200 GMZAN1
OK, reset is normal
Check U200 DATA-OUTPUT block again
NG,still no data out